Dvorák is occasionally misperceived as a lightweight from the century that produced Schubert, Brahms and Wagner. But his melodic inventiveness equaled Schubert's. In the Quintet in G Major he scored a work for string quartet plus a double bass, breaking with tradition (which called for adding a second viola or cello) and giving a welcome new tonal heft and vigor to the form. These attributes are evident in this recording by Juilliard graduate Levine and the youthful Sequoians—two Japanese women and two American men based at the California Institute of the Arts. And the G Major Quartet, written in 1895, 20 years after the Quintet, is a little-heard masterpiece—big, moving and mature. The Guarneri deliver it with the polish and fluency that has established them as one of the preeminent chamber groups.